After making a big impression on her racecourse debut at Leopardstown in June, the daughter of Deep Impact lined up in the Chesham Stakes at Royal Ascot and ran out an authoritative winner over subsequent Group Three scorer Nyaleti.
September is a best priced 11-2 favourite for next year's 1000 Guineas and looks set to step up to Group Two level this weekend.
Trainer Aidan O'Brien is responsible for six of the 11 entries, and said: "It is a big weekend at the Curragh and we are looking forward to it.
"There's nothing written in stone just yet and we'll have a look at things like the ground and how the horses work later in the week, but September and Happily would definitely be possible runners in the Debutante Stakes."
Alongside September and Happily, the Ballydoyle handler has left in Actress, Ballet Shoes, Clemmie and Magical.
The Ger Lyons-trained Black Sails could bid to bounce back from a disappointing run in the Albany Stakes at the Royal meeting.
Jim Bolger's Dawn Delivers, Brendan Duke's Feisty Katerina, the Willie McCreery-trained Mary Tudor and Shekiba from Joe Murphy's yard complete the acceptors.